The invention relates to a noise suppressor unit for installing and mounting a common mode choke for a noise suppressor in a power source module onto a circuit board of the power source module, the module being arranged onto a circuit board of a plug-in unit, wherein the noise suppressor unit comprises a holder having a bottom surface and onto which holder the common mode choke for the noise suppressor of the power source module is arranged, at least one lifting element for an assembly head or the like of an automatic assembly machine for placing the noise suppressor unit onto the circuit board of the power source module with the automatic assembly machine or the like, and at least one surface mounting element for surface mounting the common mode choke for the noise suppressor onto the circuit board of the power source module.
A power source module is a separate current delivery device positioned onto a circuit board of a plug-in unit, the device comprising a circuit board for the power source module. Owing to the structure, which comprises two stacked circuit boards, the power source module only allows the use of especially low components in order for the combination to fit into the card slot reserved for it.
The operation of a power source causes much electromagnetic noise.
The European Commission EMC directive (89/336/EEC) on electric devices determines which devices must not be disturbed by other devices and which must not disturb other devices.
In the current and future telecommunications community, the fulfilment of the requirements of the directives is of utmost importance, and also constitutes a competitive advantage. If electromagnetic noise cannot be filtered in the power source module, it propagates and may cause malfunction in the plug-in unit. As a result of this, the operation of the entire system may be disturbed.
For this reason, for preventing the propagation of noise, the interface between the power source and the plug-in unit may comprise a noise filter having, among other things, a common mode choke for a noise suppressor of the power source module. The operation of the noise filter is reciprocal.
Common mode chokes for noise suppressors in power source modules have previously been disposed on the circuit board of a plug-in unit.
Common mode chokes for noise suppressors in power source modules have previously been manually positioned onto the circuit board of the plug-in unit, and the ends of the choke coils have been soldered into openings on the circuit board of the plug-in unit.
When components are assembled onto a circuit board by modern production methods, the above-described conventional method cannot be used. A common mode choke for a noise suppressor in a power source module has to be able to be assembled automatically and surface mounted.
Such packages are commercially available that allow automated assembly and surface mounting of a common mode choke for a noise suppressor in a power source module, but owing to the two-piece holder+cover structure of the packages, the components become too high, and exceed the maximum height allowed for power source modules. One such coil component is disclosed in U.S. Pat. No. 5,307,041.